A disallowed/failed transfer is a transfer that has been rejected, typically for insufficient funds. You can tell when a transfer is disallowed/failed because you see in the Status field on the Transfers page. Disallowed/failed transfers are not displayed on the Activity page.

For a disallowed/failed transfer, you can choose to delete the transfer or change it and reschedule it. 

Note: If you close your account, scheduled transfers can become disallowed/failed transfers if they are processed after your account is closed.